Integral Garage Conversion

mca

Active Member
Nice job!

A few questions; The plasterboard you used, was it tapered edge? (it looks like it from the photos and that you filled a fair bit along the joins of the boards) Did you paint directly onto the plasterboard surface? Any special paint type or mix (i.e. watered down) used for that if so?
 

KevCarter

Standard Member
MCA,

Yes mate it is 12.5mm tapered edge plasterboard. The screen wall is sound-resistant but the rest is just standard gyproc wallboard. I read up on how to make good tapered edges beforehand. I mixed up some drywall filler in a heavy duty tub with a mixing bit on a powerful drill. It only lasts 45 minutes or so before it sets firm so you need to be sharpish about it! You run a first coat of fill over the join and I then used plasterboard tape over before the second coat. On the second coat you basically do three vertical runs, centre and either side of the join. It is quite difficult to get a nice finish but fifteen minutes with a power sander the next day and the walls are immaculate.

We didnt bother with a skim, more for cost saving because I would have wanted a pro in to do that. B&Q sell drywall sealer but it is something like £50 a tin and only looks about 2.5 - 5 litres. We read up that a water / paint mix or water / pva mix does pretty much the same thing at much lower cost so we did that. We then put two further coats of cheap white matt paint over the lot before finishing with two coats of colour.

Hope that helps.
 

mca

Active Member
Thanks, that does indeed help.

Interesting that you put a first coat of the drywall filler then tape and then a second coat of the filler, I'd have thought the tape went on first followed by the two coats of filler. Was the first coat of filler just enough to cover the join between the boards and the tape was then wide enough to cover that first coat of filler?

On the water/paint mix what ratio did you use? What paint also, well known brand or just the local DIY store's own? (Edit: Ah, you said it was a cheap paint so ignore that last question.)

Another question; the battens you used for the walls, where they 50x50mm? From what I've read elsewhere that's what's used but on trying to get some it turns out to be 47x47mm, I assume that's the 'final' size after it's planed. For what I'm looking to do I'll be in-filling between the battens with Rockwool slabs and they're supposed to be 50mm thick.

Apologies for the numerous questions...
 
Last edited:

DrH

Well-known Member
Good to see it finished in pretty quick time:smashin:

Doh with the sub connection:D

Could not bring myself to go for the black look as i listen to more music than watch films and wanted the light.

What did you watch as your premiere?

Are you well pleased with it?

Drh
 

KevCarter

Standard Member
Thanks, that does indeed help.

Interesting that you put a first coat of the drywall filler then tape and then a second coat of the filler, I'd have thought the tape went on first followed by the two coats of filler. Was the first coat of filler just enough to cover the join between the boards and the tape was then wide enough to cover that first coat of filler?

On the water/paint mix what ratio did you use? What paint also, well known brand or just the local DIY store's own? (Edit: Ah, you said it was a cheap paint so ignore that last question.)

Another question; the battens you used for the walls, where they 50x50mm? From what I've read elsewhere that's what's used but on trying to get some it turns out to be 47x47mm, I assume that's the 'final' size after it's planed. For what I'm looking to do I'll be in-filling between the battens with Rockwool slabs and they're supposed to be 50mm thick.

Apologies for the numerous questions...

I have uploaded a spreadsheet I used with costings and materials for pretty much the whole project to give you an idea of how I did it. For the most part it includes the name of the retailer and product code to find it on their website.

MEGAUPLOAD - The leading online storage and file delivery service

The first layer of drywall filler sits inside of the tapered edge join covering the narrow gap between the boards. The mesh type plasterboard tape sits into the wet filler and should be pushed lightly into it providing a good bond and a firm key for the top coat. Im no pro, this is just what I have read about, tried, and now repeat.

The paint water mix was something like 30-40% water to 70-60% paint I believe, the Mrs did the painting. Im pretty sure thats accurate though.

DrH,

I have yet to watch a blu-ray would you believe, nothing I have at the moment is jumping out at me. I am hoping to have enough cash towards the end of the month to pick a couple of new ones up. Battle LA, Sucker Punch, and Fast 5, should all be pretty impressive quality to give it a thorough review.
 

mca

Active Member
Thanks again for the answers, downloading the file now :)
 

stiscooby

Active Member
I'm looking at doing pretty much the same thing, although I will be having a window installed at the front.

I have had a few builders around who have given me quotes between £8400 & £16,000 for doing the work, and thats not even having it finished (I have someone who can plaster it for me and I can do the skirting etc)!!!!

So, I'm now considering having a go myself (I will still get the front bricked up/window installed by someone) but just do the frame work/insulation bit myself...

Regarding the celotex you used......... did you simply attach that to the wall then fix the battons on top? If so, what did you use to fix the celotex to the wall?

Also, regarding the electrics..... how did you run the cable - did you have the cable behind the celotex or did you have it in the cavity i.e. between the celotex and the plaster board? What did you do with the back boxes for the sockets, did you have to cut a bit out of the celotex or because of the cavity between the celotex and the plaster did the back boxes not actually hit the celotex?

Sorry for all the questions :D
 

KevCarter

Standard Member
I'm looking at doing pretty much the same thing...

Hello mate. I can only imagine that the majority of the cost you are being quoted for is manpower and the window wall. By putting a window in it will probably require a core of your exisiting foundation to be drilled and an engineer will need to confirm it meets the requirement to support the new wall. That is by far the most complicated part of the whole thing if you ask me and together with the cost of the window etc its likely you are looking at a few grand for that I would imagine.

You really have two options when it comes to the insulation / framing. It is entirely acceptable to build the frame against the aerated block and cut sections of Celotex to slot into each of the vertical support battons and horizontal noggins. Doing that saves losing that 6cm or so but creates mess - Celotex is a bloody nightmare to cut because particles go everywhere! I cant see any reason why wiring couldnt be put behind the Celotex in that case but dont quote me, i'm no electrician.

I chose to lose about 6cm or so in the room width in exchange for an easy ride to be honest.

Celotex/Kingspan was stood directly against the wall with the damp proof membrane of the floating floor lapped up a little behind (Block <> Membrane <> Celotex <> Timber <> Plasterboard) The Celotex used has a vapor control barrier which is maintained with barrier tape along the joins. The standard 1200x2400 boards needed a few mm trimming from each length when stood on the floor but once that was done they slotted in nice and tightly alongside one another vertically.

I stood the Celotex against the block, taped the joins, and constructed the frame flush against therbey holding the insulation in place. That gives a cavity between the Celotex and the back of your plasterboard (however deep your timber batons are) in which I ran electrics and AV. I used a hole saw in a power drill to take out 25mm cores from every vertical support close to the top with wiring passing through and secured to each batton. It is ESSENTIAL you do your reading with Part P and wiring guides because you are playing with lives at the end of the day. Make sure cables are run inside identified safe zones etc and be sure to use the correct cable for starters.

Read up and make sure you understand what you can and cant do safely. I was lucky enough to be able to break into the existing ring in my garage. If its neccesary for you to add another ring circuit to the consumer unit you will definately need a qualified sparky. Using the cavity method there is plenty of room for the socket back boxes to sit comfortably off the Celotex. I used wallboard boxes which are a doddle to fit to the fragile cut plaster edges. Best of all, they are cheap!

Consider heating too - your quote will include plumbing for a radiator I would imagine. That is a job I didnt tackle and come winter I might regret that.

Hope that helps mate.
 
Last edited:

stiscooby

Active Member
Many thanks for the detailed response :smashin:

As it happens, about 2/3rds of my garage has already been converted by previous owners but it's still cold in the winter as it hasn't been insulated etc properly so we want to pull out the partition wall to open it back up to the original size of the garage then pull all the existing stud work off the walls and re-do the lot, this time insulating it properly. There is already a radiator in there but will replace with a new one and re-locate under the new window.

I'm not going to attempt the electrics myself, there are already some sockets in there but again, I don't know how they have been connected as yet so will get a sparky in to check, then hopefully he can tell me what needs doing and I can at least run the wires in (saving some £'s ;) ) then get sparky back to connect up/test etc.

Regarding your stud work on the celotex, did you fix this to the wall (so going through the celotex and into wall behind) or did you have batons top and bottom (horizontally along floor/ceiling) and just had them fixed to this?

Finally, what did you do with the floor, did you do a suspended floor or insulate then screed etc over top?

Many thanks.
 

DrH

Well-known Member
stiscooby

When i had my garage converted the local council dictated what was required to meet the building reg's.
I would start by contacting them first.

My local council had wanted a lot insulation. Also they were very insistant on the footings along the front wall where the garage door was.

They had particular regulations for garage conversions.

DrH
 

stiscooby

Active Member
stiscooby

When i had my garage converted the local council dictated what was required to meet the building reg's.
I would start by contacting them first.

My local council had wanted a lot insulation. Also they were very insistant on the footings along the front wall where the garage door was.

They had particular regulations for garage conversions.

DrH


Yep, I have already been in contact with the local council. :smashin: Did you do yours under a 'building notice' or a 'full plan' application? I have been told I can do mine under either but I believe if I do a full plan I have to provide drawings and all sorts which seems bit over the top for a garage conversion?
 

Gliese 581c

Distinguished Member
Kev, great work on doing this yourself, it looks great.

The more and more peoples garage conversions I look at without windows really have me more and more confused. My Building reg's guys (I've talked to 2 now) insist that it should have a window installed to let in natural daylight. You dont have a window and your garage door doesnt let in daylight, your normal door is classed as borrowed daylight, so could I ask what you said to them so that you didnt have to fit a window ?
 

KevCarter

Standard Member
Apologies Gliese, I havent been subscribed to this thread and missed your question. I cant speak for why you are having problems without knowing a bit more about your existing/proposed layout but for me it was very simple.

I did not come across any stipulation whatsoever as to how much light needs to be in a room. The regs at the time I carried out the work specified only air flow/ turnover, insulation, and points of escape. I fitted standard room extraction fans (as you would find in an en suite or utility room) to cover the air flow. Due to the layout of my house, a new opening was created from the existing hallway in to the garage. Once the garage door was sealed and covered, the only access was via the house hallway, beside the front door.

As best I recall, the regs stipulated that it is acceptable not to have any secondary means of escape if the sole entry door to the room is off a hallway with direct escape to the outside world. The outside world is about four feet from the cinema door with no other obstruction. I seem to recall another stipulation about hard wired smoke alarms being situated within a set distance of the room and, again, I was fortunate that I already had this in place.

If you struggle I will have a read back through the regs and see what I can come up with. It is entirely possible though that your local authority have different standards to mine? I must say, the Stockton on tees building regs and planning guys were absolutely outstanding. I had all the support I needed without any over the top micro management.

Let me know if you need any more help or advice.
 

Peter Parker

Distinguished Member
I had some building work done recently, and one room ended up with no windows. I had applied for planning permission and it was approved after speaking with one of the approvers regarding use of the room and no windows. I did mention that commercial theatres don't have windows so why should a domestic one? I doubt that swayed the committee but once the intended usage was known and changed on the plan (changed description of the room) it was approved.

Gary
 

KevCarter

Standard Member
Several years on from this project I thought I would post an updated picture and bring the thread back from the dead in case it is of any use or inspiration to any would be DIY virgins.

mvoZn3x.jpg
 

gap69

Standard Member
Thanks for the updated picture, looks great. Is there anything that you have learned from this project that you would not repeat on another one??
 

KevCarter

Standard Member
The biggest mistake I made was a necessary evil at the time unfortunately. I originally ran a DVI cable through the stud work to a point on the right hand wall where I mounted a PC monitor. I should really have ran a HDMI cable along side it to carry audio for occasions when I wanted to game on the monitor alone without using the full sound system / projector. The DVI cable is redundant now really and so the socket looks out of place because I have removed the monitor and bracket.

I made a similar mistake running the main HDMI cable from receiver to projector. I ran a cable and tested it worked fine so sealed it all in and plastered over. A year or so later I upgraded to a 3D projector and found the cable was too poor to carry that signal. At first I could not find the problem but ultimately a better quality lead was ran on the external face of the wall to the projector and worked first time. This left the embedded cable redundant too.

I guess the message is, if you plan to run cables where possible you should consider using some sort of trunking behind the plasterboard and run a length of string through it which is accessible from any wall plates. That might provide a means of running new cable (using the string to pull through etc) without ending up with redundant buried cable or having to pull the wall apart to get it out.
 

Craig W

Novice Member
Great project ... Very informative - Well Done.

Would it be possible to upload your spreadsheet/costs again as the previous link no longer works. I know costs will have moved which I can check but keen to make sure I have covered for all materials, etc, as I'm sure you had giving the planning done in this thread.

Regards
 

ufo550

Well-known Member
Whilst congratulating the OP on his thread and excellent conversion, it is perhaps too late or irrelevant now, but I would like to add a word of caution to others who may be considering such a project.

I note that the OP has carried out the electrical work himself, acknowledging he is a DIY and not an electrician. I am an electrician.

In the early part of the thread, the OP said he had asked the building control officer, whether the electrical alterations he was considering were notifiable, and was told by the BCO it was not. Which, with what I can see to have been done, is correct. However, the point of notification, or Part P regulations, was to regulate electrical wiring works in domestic properties. As can be witnessed by this thread, Part P is not working.

I would strongly recommend, that no one considers carrying out DIY electrical alterations, additions or new work in their properties. You should employ the services of a competent electrician.

You may wish to peruse this web site;Electrical Safety in the Home & Electrical Standards | Electrical Safety First
 

SAMIPAMI

Novice Member
Hi KevCarter,

I was hoping you could help me please.
Firstly your conversion looks amazing.

I am also looking to do this but and was wondering if you could tell us how you got around the parking 3 cars out front issue with the council as we also have a 4 bed detached house.

Thanks
Sami
 

maverick177uk

Distinguished Member
Hi mate great build and something I’m going to do a couple of questions, did you have to put in the breeze block wall or could you have sealed the door and then put in a timber frame wall with insulation then plasterboard? Also do you just put the breeze blocks direct onto the garage floor?
 

The latest video from AVForums

AVForums Movies Podcast: Which is the best decade for horror movies?
Subscribe to our YouTube channel

Latest News

Hisense TVs get Disney+ on VIDAA smart OS
  • By Andy Bassett
  • Published
Astell&Kern launches entry level SR25 MKII portable music player
  • By Andy Bassett
  • Published
LG rumoured to release 97-inch OLED TV in 2022
  • By Andy Bassett
  • Published
What's new on Blu-ray (UK) for Halloween 2021
  • By Mark Costello
  • Published
AVForums Movies Podcast: 20th October 2021
  • By Phil Hinton
  • Published

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom